Height Above Ground: Cable trays should ideally be installed at least 2. 3 meters from the ceiling or any other obstructions. General Practice: Cables within the tray should be. Cable trays play a vital role in supporting electrical cables and wires in commercial, industrial, and utility installations. For proper installation, design, and maintenance, adherence to international standards is essential. One of the most recognized frameworks globally is the IEC standard for. Although BS 7671 touches on the subject of cable supports, it does not detail specifically what these support distances should be. 8 (Other Mechanical Stresses (AJ)) in that document provides requirements for cable support.